Thyrotropin Receptor Antagonism by a Novel Small Molecule: Preclinical Observations.

Treatment of Graves' hyperthyroidism (GH) and Graves' orbitopathy (GO) is far from adequate, and hence, new substances that specifically target the autoantigens in GH/GO are warranted. This study determined the preclinical efficacy of SYD5115, a novel low-molecular-weight compound that inhibits the thyrotropin receptor (TSH-R). The TSH-R inhibiting capability of SYD5115 was tested through stimulation of wild-type and chimeric TSH-R expressed in Chinese hamster ovary (CHO) cells using two functional (stimulatory and blocking) cell-based TSH-R-Ab bioassays.

Discovery of SYD5115, a novel orally active small molecule TSH-R antagonist.

The thyrotropin receptor (TSH-R) regulates the thyroid gland and is normally activated by thyrotropin. In patients with Graves' disease, TSH-R is also stimulated by stimulatory TSH-R autoantibodies leading to hyperthyroidism. In this paper, we describe the discovery of SYD5115 (67), a novel small molecule TSH-R antagonist with nanomolar potency.